evil: fix dladdr() implementation, add 2 unit tests for evil.

@fix

Signed-off-by: Cedric BAIL <cedric@osg.samsung.com>

2 files changed, 170 insertions, 48 deletions

diff --git a/src/lib/evil/dlfcn.c b/src/lib/evil/dlfcn.c
index c220003de6..ae8687ebf5 100644
--- a/src/lib/evil/dlfcn.c
+++ b/src/lib/evil/dlfcn.c
@@ -171,21 +171,67 @@ dlsym(void *handle, const char *symbol)
    return fp;
 }
 
+char *
+dlerror (void)
+{
+   if (!_dl_err_viewed)
+     {
+        _dl_err_viewed = 1;
+        return _dl_err;
+     }
+   else
+     {
+        if (_dl_err)
+          free(_dl_err);
+        return NULL;
+     }
+}
+
+#ifdef _GNU_SOURCE
+
+static char _dli_fname[MAX_PATH];
+static char _dli_sname[MAX_PATH]; /* a symbol should have at most 255 char */
+
+static int
+_dladdr_comp(const void *p1, const void *p2)
+{
+   return ( *(int *)p1 - *(int *)p2);
+}
+
 int
 dladdr (const void *addr EVIL_UNUSED, Dl_info *info)
 {
-   TCHAR  tpath[PATH_MAX];
+   TCHAR tpath[PATH_MAX];
    MEMORY_BASIC_INFORMATION mbi;
-   char  *path;
+   unsigned char *base;
+   char *path;
    size_t length;
-   int    ret = 0;
+
+   IMAGE_NT_HEADERS *nth;
+   IMAGE_EXPORT_DIRECTORY *ied;
+   DWORD *addresses;
+   WORD *ordinals;
+   DWORD *names;
+   DWORD *tmp;
+   DWORD res;
+   DWORD rva_addr;
+   DWORD i;
 
    if (!info)
      return 0;
 
-   length = VirtualQuery(addr, &mbi, sizeof(mbi));
-   if (!length)
-     return 0;
+   info->dli_fname = NULL;
+   info->dli_fbase = NULL;
+   info->dli_sname = NULL;
+   info->dli_saddr = NULL;
+
+   /* Get the name and base address of the module */
+
+   if (!VirtualQuery(addr, &mbi, sizeof(mbi)))
+     {
+        _dl_get_last_error("VirtualQuery returned: ");
+        return 0;
+     }
 
    if (mbi.State != MEM_COMMIT)
      return 0;
@@ -193,49 +239,110 @@ dladdr (const void *addr EVIL_UNUSED, Dl_info *info)
    if (!mbi.AllocationBase)
      return 0;
 
-   ret = GetModuleFileName((HMODULE)mbi.AllocationBase, (LPTSTR)&tpath, PATH_MAX);
-   if (!ret)
-     return 0;
+   base = (unsigned char *)mbi.AllocationBase;
 
-#ifdef UNICODE
+   if (!GetModuleFileName((HMODULE)base, (LPTSTR)&tpath, PATH_MAX))
+     {
+        _dl_get_last_error("GetModuleFileName returned: ");
+        return 0;
+     }
+
+# ifdef UNICODE
    path = evil_wchar_to_char(tpath);
-#else
+# else
    path = tpath;
-#endif /* ! UNICODE */
+# endif /* ! UNICODE */
 
-   length = strlen (path);
+   length = strlen(path);
    if (length >= PATH_MAX)
      {
        length = PATH_MAX - 1;
        path[PATH_MAX - 1] = '\0';
      }
 
-   EVIL_PATH_SEP_UNIX_TO_WIN32(path);
+   memcpy(_dli_fname, path, length + 1);
+   info->dli_fname = (const char *)_dli_fname;
+   info->dli_fbase = base;
 
-   memcpy (info->dli_fname, path, length + 1);
-   info->dli_fbase = NULL;
-   info->dli_sname = NULL;
-   info->dli_saddr = NULL;
+# ifdef UNICODE
+        free(path);
+# endif /* ! UNICODE */
 
-#ifdef UNICODE
-   free (path);
-#endif /* ! UNICODE */
+   /* get the name and the address of the required symbol */
 
-   return 1;
-}
+   if (((IMAGE_DOS_HEADER *)base)->e_magic != IMAGE_DOS_SIGNATURE)
+     {
+        SetLastError(1276);
+        return 0;
+     }
 
-char *
-dlerror (void)
-{
-   if (!_dl_err_viewed)
+   nth = (IMAGE_NT_HEADERS *)(base + ((IMAGE_DOS_HEADER *)base)->e_lfanew);
+   if (nth->Signature != IMAGE_NT_SIGNATURE)
      {
-        _dl_err_viewed = 1;
-        return _dl_err;
+        SetLastError(1276);
+        return 0;
      }
-   else
+
+   /* no exported symbols ? it's an EXE and we exit without error */
+   if (nth->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT].VirtualAddress == 0)
      {
-        if (_dl_err)
-          free(_dl_err);
-        return NULL;
+        return 1;
+     }
+
+   /* we assume now that the PE file is well-formed, so checks only when needed */
+   ied = (IMAGE_EXPORT_DIRECTORY *)(base + nth->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT].VirtualAddress);
+   addresses = (DWORD *)(base + ied->AddressOfFunctions);
+   ordinals = (WORD *)(base + ied->AddressOfNameOrdinals);
+   names = (DWORD *)(base + ied->AddressOfNames);
+
+   /* the addresses are not ordered, so we need to order them */
+   tmp = malloc(ied->NumberOfFunctions * sizeof(DWORD));
+   if (!tmp)
+     {
+        SetLastError(8);
+        return 0;
+     }
+
+   memcpy(tmp, addresses, ied->NumberOfFunctions * sizeof(DWORD));
+   qsort(tmp, ied->NumberOfFunctions, sizeof(DWORD), _dladdr_comp);
+   rva_addr = (unsigned char *)addr - base;
+   res = (DWORD)(-1);
+   for (i = 0; i < ied->NumberOfFunctions; i++)
+     {
+        if (tmp[i] < rva_addr)
+          continue;
+
+        res = tmp[i];
+        break;
      }
+
+   /* if rva_addr is too high, we store the latest address */
+   if (res == (DWORD)(-1))
+     res = tmp[ied->NumberOfFunctions - 1];
+
+   free(tmp);
+
+   for (i = 0; i < ied->NumberOfNames; i++)
+     {
+        if (addresses[ordinals[i]] == res)
+          {
+             char *name;
+
+             name = (char *)(base + names[i]);
+             length = strlen(name);
+             if (length >= PATH_MAX)
+               {
+                  length = PATH_MAX - 1;
+                  name[PATH_MAX - 1] = '\0';
+               }
+             memcpy(_dli_sname, name, length + 1);
+             info->dli_sname = (const char *)_dli_sname;
+             info->dli_saddr = base + res;
+             return 1;
+          }
+     }
+
+   return 0;
 }
+
+#endif /* _GNU_SOURCE */
diff --git a/src/lib/evil/dlfcn.h b/src/lib/evil/dlfcn.h
index 21de0b8ccc..349a9b4356 100644
--- a/src/lib/evil/dlfcn.h
+++ b/src/lib/evil/dlfcn.h
@@ -64,30 +64,40 @@ x * This header provides functions to load and unload dynamic-link
  */
 #define RTLD_NODELETE 0x01000  /* do not delete object when closed.  */
 
+#ifdef _GNU_SOURCE
+
 /**
  * @def RTLD_DEFAULT
  * Symbols are searched in all the DLL opened by the current process.
+ * This symbol is defined only when _GNU_SOURCE was defined before
+ * including dlfcn.h.
  */
 #define RTLD_DEFAULT ((void*)1) /* search the symbol on all the DLL of the current process */
 
 /**
  * @typedef Dl_info
  * @brief A structure that stores infomation of a calling process.
+ * This typedef is defined only when _GNU_SOURCE was defined before
+ * including dlfcn.h.
  */
 typedef struct Dl_info Dl_info;
 
 /**
  * @struct Dl_info
  * @brief A structure that stores infomation of a calling process.
+ * This structure is defined only when _GNU_SOURCE was defined before
+ * including dlfcn.h.
  */
 struct Dl_info
 {
-   char        dli_fname[PATH_MAX];  /**< Filename of defining object */
-   void       *dli_fbase;            /**< Load address of that object */
-   const char *dli_sname;            /**< Name of nearest lower symbol */
-   void       *dli_saddr;            /**< Exact value of nearest symbol */
+   const char *dli_fname;  /**< Filename of defining object */
+   void       *dli_fbase;  /**< Load address of that object */
+   const char *dli_sname;  /**< Name of nearest lower symbol */
+   void       *dli_saddr;  /**< Exact value of nearest symbol */
 };
 
+#endif /* _GNU_SOURCE */
+
 /**
  * @brief Map a specified executable module (either a .dll or .exe file)
  * into the address space of the user process.
@@ -197,30 +207,35 @@ EAPI int   dlclose(void* handle);
  */
 EAPI void *dlsym(void* handle, const char* symbol);
 
+#ifdef _GNU_SOURCE
+
 /**
- * @brief Get the location of the current process (.exe)
+ * @brief Resolve module and function pointers from the given function
+ * pointer address.
  *
- * @param addr Unused.
- * @param info Pointer to the Dl_info to fill.
+ * @param addr A function pointer.
+ * @param info Pointer to the #Dl_info to fill.
  * @return 1 on success, 0 otherwise.
  *
- * Fill the dli_fname member of @p info with the absolute name
- * of the current calling process (.exe file that is executed).
- * All other members are set to @c NULL.
+ * Fill @p info with the absolute name of the module which has the
+ * fonction pointer @p addr, the base address of that module, the name
+ * and address of the symbol. If no symbol matching @p addr could be
+ * found (as in an EXE file), then dli_sname and dli_saddr are set to
+ * NULL and the function returns 1. See #Dl_info for more informations.
  *
- * Contrary to the unix function, the full name of the shared
- * library is not returned, but insted the full name of the current
- * calling process (.exe file).
+ * This function is available only when _GNU_SOURCE was defined before
+ * including dlfcn.h.
  *
  * Conformity: None.
  *
- * Supported OS: Windows Vista, Windows XP or Windows 2000
- * Professional.
+ * Supported OS: Windows Vista, Windows XP.
  *
  * @ingroup Evil_Dlfcn
  */
 EAPI int dladdr (const void *addr, Dl_info *info);
 
+#endif /* _GNU_SOURCE */
+
 /**
  * @brief Get diagnostic information
  *